leetcode--Palindrome Partitioning

Given a string s, partition s such that every substring of the partition is a palindrome.

Return all possible palindrome partitioning of s.

For example, given s = "aab",
Return

  [
    ["aa","b"],
    ["a","a","b"]
  ]

  Discuss

public class Solution {
    public ArrayList<ArrayList<String>> partition(String s) {
         ArrayList<ArrayList<String> > result = new ArrayList<ArrayList<String> >();
		int len = s.length();
		if(len > 0){
			for(int i = 0; i < len; ++i){				
				if(isPalindrome(s.substring(0, i + 1))){
					ArrayList<ArrayList<String> > temp = partition(s.substring(i + 1, len));
					int size = temp.size();
					if(size > 0){
						while(!temp.isEmpty()){
							ArrayList<String> aPartition = new ArrayList<String>();
							aPartition.add(s.substring(0, i + 1));
							ArrayList<String> alist = temp.remove(0); 
							aPartition.addAll(alist);
							result.add(aPartition);
						}
					}
					else{
						ArrayList<String> alist = new ArrayList<String>();
						alist.add(s.substring(0,i + 1));
						result.add(alist);
					}
				}
			}			
		}
		return result;
    }
	
	public boolean isPalindrome(String s){
		boolean isPal = true;
		for(int i = 0,j = s.length() - 1; i <= j; ++i, --j){
			if(s.charAt(i) != s.charAt(j)){
				isPal = false;
				break;
			}
		}
		return isPal;
    }
}